Allow templates with multiple test suites to run in sequence in same VM

Some templates have multiple test suites. Each test suite is executed on its own VM instance. Most of the test suites don't have any affect on each other if they were to run on the same VM. Instead of creating and destroying a new VM per test suite, we should have the ability to run them in sequence on the same VM. For longer running tests or tests that make changes to the VM, we should not lose the ability to run tests how they currently execute.